package com.katsu.myapplib.http;

import java.io.IOException;
import java.io.InputStream;
import java.security.KeyManagementException;
import java.security.KeyStore;
import java.security.KeyStoreException;
import java.security.NoSuchAlgorithmException;
import java.security.UnrecoverableKeyException;
import java.security.cert.CertificateException;
import java.security.cert.CertificateFactory;
import java.security.cert.X509Certificate;

import javax.net.ssl.HostnameVerifier;
import javax.net.ssl.KeyManager;
import javax.net.ssl.KeyManagerFactory;
import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLSession;
import javax.net.ssl.SSLSocketFactory;
import javax.net.ssl.TrustManager;
import javax.net.ssl.TrustManagerFactory;
import javax.net.ssl.X509TrustManager;

public class HttpCert {

    public static class SSLParams {

        public SSLSocketFactory sSLSocketFactory;

        public X509TrustManager trustManager;

    }

    public static SSLParams getSslSocketFactory(InputStream[] certificates, InputStream bksFile, String password, String type) {

        SSLParams sslParams = new SSLParams();

        try {

            TrustManager[] trustManagers = prepareTrustManager(certificates);

            KeyManager[] keyManagers = prepareKeyManager(bksFile, password, type);

            SSLContext sslContext = SSLContext.getInstance("TLS");

            X509TrustManager trustManager = null;

            if (trustManagers != null) {

                trustManager = new MyTrustManager(chooseTrustManager(trustManagers));

            } else {

                trustManager = new UnSafeTrustManager();

            }
            sslContext.init(keyManagers, new TrustManager[] { trustManager }, null);

            sslParams.sSLSocketFactory = sslContext.getSocketFactory();

            sslParams.trustManager = trustManager;

            return sslParams;

        } catch (NoSuchAlgorithmException e) {

            throw new AssertionError(e);

        } catch (KeyManagementException e) {

            throw new AssertionError(e);

        } catch (KeyStoreException e) {

            throw new AssertionError(e);

        }

    }

    @SuppressWarnings("unused")
    private class UnSafeHostnameVerifier implements HostnameVerifier {

        @Override
        public boolean verify(String hostname, SSLSession session) {

            return true;

        }

    }

    private static class UnSafeTrustManager implements X509TrustManager {

        @Override
        public void checkClientTrusted(X509Certificate[] chain, String authType) throws CertificateException {}

        @Override
        public void checkServerTrusted(X509Certificate[] chain, String authType) throws CertificateException {}

        @Override
        public X509Certificate[] getAcceptedIssuers() {

            return new X509Certificate[] {};

        }

    }

    private static TrustManager[] prepareTrustManager(InputStream... certificates) {

        if (certificates == null || certificates.length <= 0){

            return null;

        }

        try {

            CertificateFactory certificateFactory = CertificateFactory.getInstance("X.509");

            KeyStore keyStore = KeyStore.getInstance(KeyStore.getDefaultType());

            keyStore.load(null);

            int index = 0;

            for (InputStream certificate : certificates) {

                String certificateAlias = Integer.toString(index++);

                keyStore.setCertificateEntry(certificateAlias, certificateFactory.generateCertificate(certificate));

                try {

                    if (certificate != null){

                        certificate.close();

                    }

                } catch (IOException e) {}

            }

            TrustManagerFactory trustManagerFactory = null;

            trustManagerFactory = TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm());

            trustManagerFactory.init(keyStore);

            TrustManager[] trustManagers = trustManagerFactory.getTrustManagers();

            return trustManagers;

        } catch (NoSuchAlgorithmException e) {

            e.printStackTrace();

        } catch (CertificateException e) {

            e.printStackTrace();

        } catch (KeyStoreException e) {

            e.printStackTrace();

        } catch (Exception e) {

            e.printStackTrace();

        }

        return null;

    }

    private static KeyManager[] prepareKeyManager(InputStream bksFile, String password, String type) {

        try {

            if (bksFile == null || password == null) {

                return null;

            }

            KeyStore clientKeyStore = KeyStore.getInstance(type);

            clientKeyStore.load(bksFile, password.toCharArray());

            KeyManagerFactory keyManagerFactory = KeyManagerFactory.getInstance(KeyManagerFactory.getDefaultAlgorithm());

            keyManagerFactory.init(clientKeyStore, password.toCharArray());

            return keyManagerFactory.getKeyManagers();

        } catch (KeyStoreException e) {

            e.printStackTrace();

        } catch (NoSuchAlgorithmException e) {

            e.printStackTrace();

        } catch (UnrecoverableKeyException e) {

            e.printStackTrace();

        } catch (CertificateException e) {

            e.printStackTrace();

        } catch (IOException e) {

            e.printStackTrace();

        } catch (Exception e) {

            e.printStackTrace();

        }

        return null;

    }

    private static X509TrustManager chooseTrustManager(TrustManager[] trustManagers) {

        for (TrustManager trustManager : trustManagers) {

            if (trustManager instanceof X509TrustManager) {

                return (X509TrustManager) trustManager;

            }

        }

        return null;

    }

    private static class MyTrustManager implements X509TrustManager {

        private X509TrustManager defaultTrustManager;

        private X509TrustManager localTrustManager;

        public MyTrustManager(X509TrustManager localTrustManager) throws NoSuchAlgorithmException, KeyStoreException {

            TrustManagerFactory var4 = TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm());

            var4.init((KeyStore) null);

            defaultTrustManager = chooseTrustManager(var4.getTrustManagers());

            this.localTrustManager = localTrustManager;

        }

        @Override
        public void checkClientTrusted(X509Certificate[] chain, String authType) throws CertificateException {}

        @Override
        public void checkServerTrusted(X509Certificate[] chain, String authType) throws CertificateException {

            try {

                defaultTrustManager.checkServerTrusted(chain, authType);

            } catch (CertificateException ce) {

                localTrustManager.checkServerTrusted(chain, authType);

            }

        }

        @Override
        public X509Certificate[] getAcceptedIssuers() {

            return new X509Certificate[0];

        }

    }
}
